Alexander Litvinenkos widow, Marina Litvinenko, right, and her solicitor Elena Tsirlina arrive outside the Royal Courts of Justice in London, the UK, on Tuesday. Picture: EPA / FACUNDO ARRIZABALAGA on Business Day Live

AFP on News24

LONDON — Russian President Vladimir Putin "probably approved" the killing of former KGB agent Alexander Litvinenko in London, a British inquiry into his death by radiation poisoning found on Thursday.

Litvinenko, a prominent Kremlin critic, died in 2006, three weeks after drinking green tea laced with radioactive polonium at an upmarket London hotel.

Andrei Lugovoi and Dmitri Kovtun, two Russians identified as prime suspects by British police, probably carried out the poisoning under the instruction of Russian security services, the inquiry said.

British Prime Minister David Cameron’s office called the findings "extremely disturbing" but the government did not announce sanctions in response, instead summoning Moscow’s ambassador to London. It did, however, impose asset freezes on the two alleged perpetrators named by the inquiry.

Litvinenko’s wife, Marina, accompanied by her son Anatoly, welcomed the finding.

She has spent years pushing for a public inquiry to be held and had called for sanctions against Russia and a travel ban on Mr Putin.

"I’m very pleased that the words my husband spoke on his deathbed when he accused Mr Putin of his murder have been proved true in an English court," she said. "I can’t say it is what I hoped for but I really appreciate it.

"I’m calling immediately for exclusion from the UK of all Russian intelligence operatives whether from the FSB, who murdered Sasha, or from other Russian agencies based in the London embassy," she said.

"I’m also calling for the imposition of targeted economic sanctions and travel bans against named individuals, including Mr Patrushev and Mr Putin," she said, adding that the British government had promised action.

"We had no reason to expect that the final findings of the politically motivated and extremely nontransparent process … would suddenly become objective and unbiased," foreign ministry spokeswoman Maria Zakharova said in a statement.

Mr Lugovoi, now a far-right pro-Putin legislator in Russia, called the report absurd.

Earlier, inquiry lead Judge Robert Owen said he was sure Mr Lugovoi and Mr Kovtun placed polonium-210 in the teapot at London’s Millennium Hotel’s Pine Bar, where they met Litvinenko on November 1 2006.

"The FSB operation to kill Litvinenko was probably approved by Mr (Nikolai) Patrushev and also by President Putin," the report said.

Mr Patrushev is a former director of the FSB, the successor organisation to the Soviet-era KGB spy agency, and has been a key security official since 2008.

Polonium-210 is a rare radioactive isotope only available in closed nuclear facilities.

The report, which contained classified evidence redacted from the version made public, said this suggested that Mr Lugovoi and Mr Kovtun "were acting for a state body rather than a criminal organisation".

There was no evidence to suggest that either Mr Lugovoi or Mr Kovtun had any personal reason to kill Litvinenko and they were likely to be acting under FSB direction, Judge Owen said.

Shortly after the report was published, London’s Metropolitan Police issued a statement stressing they still wanted the pair to be extradited. "Our objective will always be to put them before a criminal court."

Litvinenko, a former KGB agent turned freelance investigator who also worked for British intelligence, accused Mr Putin of ordering his killing in a statement before he died on November 23 2006.

Judge Owen said there were powerful motives for the killing. Litvinenko was seen as having betrayed the FSB and had regularly targeted Mr Putin with "highly personal public criticism", including an accusation of paedophilia.

Britain’s government announced the inquiry in July 2014, just days after the downing of a Malaysian passenger jet over eastern Ukraine — a tragedy blamed on Russia’s involvement in the conflict in the region — in what was seen as a way of punishing Russia. It started work in January last year.

Britain’s response to the inquiry’s findings fell short of the sanctions, which some had called for.

Home Secretary Theresa May stressed the importance of Russia’s role in talks attempting to resolve the conflict in Syria in a statement on the inquiry to the House of Commons.

She said Britain would make "senior representations" over Moscow’s "failure to co-operate and provide satisfactory answers".

"The conclusion that the Russian state was probably involved in the murder of Mr Litvinenko is deeply disturbing," Ms May told parliament. "This was a blatant and unacceptable breach of the most fundamental tenets of international law and of civilised behaviour."

Urging Putin and Russia to "make a positive contribution to global security and stability," May added: "They can, for example, play an important role in defeating Daesh," she said, using another term for the Islamic State group.